US4327043A - Tower packing element - Google Patents

Tower packing element Download PDF

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Publication number
US4327043A
US4327043A US06/219,311 US21931180A US4327043A US 4327043 A US4327043 A US 4327043A US 21931180 A US21931180 A US 21931180A US 4327043 A US4327043 A US 4327043A
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United States
Prior art keywords
packing
end portions
tongues
tower
intermediate portion
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
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US06/219,311
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English (en)
Inventor
Max Leva
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Individual
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Individual
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Publication date
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Priority to US06/219,311 priority Critical patent/US4327043A/en
Priority to DE19813150216 priority patent/DE3150216A1/de
Priority to GB8138618A priority patent/GB2089679B/en
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J19/30—Loose or shaped packing elements, e.g. Raschig rings or Berl saddles, for pouring into the apparatus for mass or heat transfer
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/30—Details relating to random packing elements
    • B01J2219/304—Composition or microstructure of the elements
    • B01J2219/30466—Plastics
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S261/00—Gas and liquid contact apparatus
    • Y10S261/72—Packing elements

Definitions

  • This invention relates to a new tower packing element which is used in randomly poured beds contained in towers, to bring about mass transfer between gaseous or vaporous and liquid phases.
  • the randomly poured bed or packing is employed in vertical vessels with the gas or vapor phase entering the packed bed from the bottom of the packed bed and rising upwardly.
  • the liquid is administered to the top of the packed bed, usually by means of a liquid distributor, and through the force of gravity runs downwardly.
  • Pat. No. 2639909 are significantly higher, because due to the less symmetrical shape embodied in the saddle element of U.S. Pat. No. 2639909, there is no nesting of pieces. Hence the surface area offered to mass transfer is more readily accessible to liquid and gas contacting. The extent of irregularity of shape which is provided by a tower packing element is thus noted to have an important bearing on the resulting mass transfer efficiency.
  • the packing elements composing the packed bed must comprise such features that are conducive to provide an efficient liquid distribution throughout the packed bed.
  • the tongues contained in the interior of the slotted rings are largely ineffective as far as providing an improved internal liquid flow pattern through the packed bed is concerned. This is so because with the tongues all inside of the rings, the tongues are somewhat confined and not sufficiently exposed, therefore do not make any significant contact with adjoining packing pieces in the packed bed.
  • the packing elements in the packed bed should be thoroughly interlocked with each other, so that the downwardly acting weight force of the packed bed is randomly distributed across the tower cross-section. In this way the weight force acting laterally on the tower wall will be minimized. This will also eliminate the danger of crushing of the lowermost packing layers in the bottom of a high packed bed.
  • the ability of adjacent packing elements to interlock will permit the packing elements to be made of thinner gage material which is important as far as the economics of the structure is concerned.
  • the physical length, L should be such that with the prevailing curvatures of the individual zones, interconnected as defined above, the normals to the tangents in regard to the ends of the bent strip should define an angle that varies between zero to about 88 degrees.
  • bent strip thus defined should be provided with slots and tongues, which latter point away from the bent strip in a manner to be described more fully hereinafter.
  • FIG. 1 is a side view which shows the various important main features of the invention
  • FIG. 2 shows a modification of FIG. 1 and details of the bent strip of a somewhat different design
  • FIG. 3 shows another modification of the geometry of the bent strip
  • FIG. 4 shows still another modification of the bent strip
  • FIG. 5 shows still another modification of the bent strip
  • FIG. 6 shows still a further modification of the bent strip of FIG. 5;
  • FIG. 7 shows still another modification of the bent strip
  • FIG. 8 shows a somewhat different modification of the bent strip
  • FIG. 9 shows still another variation of the geometry of the bent strip
  • FIG. 10 shows a final variation in the design of the bent strip still in accord with the spirit of the invention.
  • FIG. 11 shows, in section along line 11--11 of FIG. 12, characteristic slot and tongue details
  • FIG. 12 is a side elevation of FIG. 11 showing further details of the invention.
  • FIG. 13 shows further details of slots and tongues which Figure is an elevation in section along line 13--13 of FIG. 14;
  • FIG. 14 is another side elevation of a typical packing element showing further details embodied in the invention.
  • FIG. 15 is another sectional elevation showing further construction details.
  • FIG. 16 shows another side elevation of a typical form of the invention.
  • the three separate zones of the curved strip are denoted by numerals 1, 1a and 1b.
  • Point of inflection X 1 separates zone 1a from zone 1
  • point of inflection X 2 separates zone 1b from zone 1.
  • Tangents T 1 and T 2 pertaining to the ends of the bent strip as defined by length L are indicated, as well as the corresponding normals N 1 and N 2 . It will be seen that for this design, the normals are parallel to each other, which means that the angle between the normals is zero degrees.
  • FIG. 1 shows three tongues, denoted by I,II and III. It will be noted that all tongues point downwardly. However, since zones 1a and 1b exhibit convex curvatures, when viewed from below, it is seen that tongues I and III point away from the centers C 1 and C 2 of zones 1a and 1b. As far as zone 1 and depending tongue II are concerned, the reverse is true, and tongue II points in the direction of C 2 the center of zone 1.
  • This characteristic arrangement of tongues, in relation to zones from which they depend and the resulting pattern, is an important feature of the invention, as through employment of zones having curvatures in opposite directions and tongues depending from the zones, as shown, a highly unsymmetrical packing element is generated that will lead to a highly randomized packed bed. This was found important in greatly enhancing the bed stability and encourages improved internal liquid distribution, required for optimum mass transfer performance.
  • tongues I, II and III extend somewhat beyond the lower edge of the packing element. Whereas it is not required that any or all tongues must extend as far down as are shown in FIG. 1, it has generally been found that long tongues will lead to improved mass transfer rates.
  • FIGS. 2 to 10 certain variations in the designs of the bent strip are brought forth, all in accord with the spirit of the invention. For purposes of elucidating these features more clearly, tongues and slots, always present in any packing elements discussed here, have been omitted for convenience.
  • FIG. 2 shows a somewhat wider packing element than FIG. 1, but still clearly within the spirit of the invention.
  • zones 2a and 2 are separated by point of inflection X 1
  • point of inflection X 2 separates zones 2 and 2b.
  • the curvatures of zones 2a and 2, as well as 2 and 2b are, as is required by the invention, in opposite directions, respectively.
  • Normals N 1 and N 2 to tangents T 1 and T 2 are shown, and it will be noted that angle ⁇ , defined by intersection of normals N 1 and N 2 , is within the required specifications.
  • FIG. 3 shows another modification of the bent strip. It will be noted that zones 4a and 4b are appreciably shorter than the corresponding zones in FIGS. 1 and 2. The essential feature is, however, that there are the two points of inflection X 1 and X 2 separating the three zones from each other. It will be noted that angle ⁇ formed by the normals N 1 and N 2 is within the specifications, and that this angle does actually fix the arcuate lengths of zones 4a and 4b.
  • FIG. 4 showing another modification of design of the bent strip, embodies a design which adds another measure of non-symmetry to the packing element.
  • FIGS. 1 to 3 the outer zones of curvature were of the same arcuate lengths, this is no longer the case with the following FIGS. 4 to 10.
  • FIG. 4 displays the two required points of inflection X 1 and X 2 .
  • the angle ⁇ generated by the two normals N 1 and N 2 is seen to be within the required specifications.
  • FIG. 5 Another highly asymmetric design is shown in FIG. 5.
  • the points of inflection X 1 and X 2 are seen to separate the three zones of curvature, 8a, 8 and 8b. It may be seen that zone 8b is quite short in comparison with zone 8a. For that reason one may perhaps not have any tongues depending from 8b, or even from the longer end portions, such as 8a.
  • FIG. 11 is a sectional view taken along line 11--11 of FIG. 12 of a typical packing element.
  • the expanse of the bent strip is denoted by numeral 22, and it is clearly apparent that there are two points of inflection, as are required by the invention.
  • the bent strip is provided with slots 23,24 and 25.
  • tongues 26, 27 and 28 Depending from the slots are tongues 26, 27 and 28.
  • the tongues are bent and are all of the same arcuate lengths as the slots from which they depend. This being the case, the slots and tongues have been formed integrally by one and the same operation. Such a process is usually employed when working with metals, and the material composing the tongues was originally contained in the slots prior to formation of the tongues.
  • the diameter of the central curved zone is indicated by D, whereas the total length of the packing element is given by L.
  • the ratio of L/D is equal to two.
  • the peripheral tongues 27 and 28 being smaller than the central tongues 26, one would expect the peripheral tongues 27 and 28 to occupy an inferior role in the process of gas-liquid contacting.
  • L By virtue of an adequate choice of length L, it becomes possible to expose the smaller tongues 27 and 28 more effectively and thus render them more effective than would be the case with a lesser value of L.
  • the importance of the small tongues 27 and 28 is enhanced further because they depend away from surfaces which are convex rather than concave.
  • FIG. 12 shows a side elevation of FIG. 11.
  • the bent strip is denoted by numeral 29 and the slots are identified by 30.
  • Two rows of slots are provided with tongues progressing in reverse direction, as shown in FIG. 11.
  • the width of the packing element of FIG. 12 is indicated by W.
  • W The width of the packing element of FIG. 12 is determined to an important extent by the number of rows of slots which are contained in parallel in the element. However, it is important that the width will not be too narrow as otherwise undesirable arrangements of the packing elements in the packed bed will result.
  • the ratio of L/W can vary from 0.5 to 4.0. For best results, however, it was found that the ratio should be between 0.75 and 3.0.
  • FIG. 13 is a sectional view of another typical packing element as viewed along line 13--13 of FIG. 14.
  • the bent strip is denoted by numeral 31 and the slots in the strip by numerals 32, 33 and 34.
  • Tongues 35 and 36 depending from the small slots 33 and 34, are essentially of the same arcuate length as the depending slots.
  • tongues 37 depending from the central larger slots, are seen to be longer arcuately than the arcuate lengths of slots 33. The material composing these tongues 37 was therefore not originally contained in the slots before forming.
  • both the bent strip 31 as well as tongues 37 are provided with small diameter holes 38 and 39, respectively. Provision of such holes or perforations is frequently an important requirement, especially when the packings are used in applications that call for elevated liquid irrigation rates. In such instances, provision of such holes as indicated will yield higher mass transfer rates for two important reasons. Firstly because provision of holes 38 and 39 will encourage a faster run-off of liquid away from the packing surface and tongues, the liquid hold-up in the column is reduced and secondly, by passing the liquid downwardly by way of the many small streamlets which will result from these perforations, additional contacting surface between gas and liquid is generated. Both features will have beneficial effects as far as improvement of mass transfer rates are concerned. Finally, provision of such holes in conjunction with the very long tongues as are contained in the packing elements becomes especially desirable as otherwise stagnant liquid pools may form which would have additional adverse effects on mass transfer.
  • FIG. 14 shows a side elevation of the packing element shown in section in FIG. 13.
  • the bent strip is denoted by numeral 40, looking on the bent strip edgewise. Slots are indicated by numeral 41 and the holes, perforating the bent strip are indicated by numeral 42. These holes or perforations are in most cases circular. However, it would be in the spirit of the invention to provide holes of other geometric shapes as well. The diameters of these holes may become of importance. In most cases they are, however, envisioned as relatively small, say of a few millimeters in diameter, in order to be effective for diverting the liquid away in the form of small streamlets.
  • FIG. 15 shows another design of the packing element.
  • the bent strip is denoted by numeral 43, and three relatively large slots are denoted by numerals 44, 45 and 46.
  • tongues 47 depending from slots 44 are actually longer than the arcuate lengths of slots 44, whereas tongues 48 and 49 are arcuately smaller than the corresponding slots 45 and 46. It is also indicated that tongues 47 are downwardly tapered.
  • the packing element described in FIG. 15 contains also strengthening rib 50, extending inwardly, as well as strengthening ribs 51 and 52, extending outwardly. For best results it has been found that the depth of the strengthening ribs, as denoted by letter “R”, should not be less than one sixth of the largest expanse of a rib, as denoted by letter "D".
  • the packing element described in FIG. 15 is a modification of that shown in FIG. 13 and is most conveniently made of plastics, using the normal methods of injection molding or similar techniques. Although not indicated, a piece of the design of FIG. 15 would preferably be equipped with a multitude of relatively small diameter holes as has already been described in connection with FIGS. 13 and 14, to minimize liquid hold-up and enhance mass transfer efficiency.
  • FIG. 16 shows a final design of a packing element.
  • the bent strip is denoted by numeral 53 and the line along which the points of inflection progress is indicated by numeral 54.
  • Two parallel rows of slots denoted by numerals 55 are indicated, from which tongues (not shown) depend.
  • the element described in FIG. 16 contains an additional feature, namely cut-out 56, generated by the up-turned edges 57 of a central portion of the bent strip. Provision of such a cut-out was found to have a significant effect on the performance of the packing by both increasing the capacity of the packed bed to handle larger quantities of gases and liquids, as well as by improving additional randomness in the bed and improved mass transfer.
  • the central cut-out 56 would normally extend around the central curved zone of the packing element only and down to about the line which defines the points of inflection.
  • a packing element of the design shown in FIG. 16 may, of course, also be equipped with small diameter holes or perforations, both in the bent strip as well as in the tongues.
  • the design can be made readily of metals, as well as plastics through the normal methods of injection molding.
  • tongues when struck out from slots are of the same material as the packing element, particularly when molded of plastic material, in other instances they may be of a different material, also they may be longer or shorter than the slots from which they emerge.

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  • Chemical & Material Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Physical Or Chemical Processes And Apparatus (AREA)
  • Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)
US06/219,311 1980-12-22 1980-12-22 Tower packing element Expired - Lifetime US4327043A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
US06/219,311 US4327043A (en) 1980-12-22 1980-12-22 Tower packing element
DE19813150216 DE3150216A1 (de) 1980-12-22 1981-12-18 Fuellkoerper
GB8138618A GB2089679B (en) 1980-12-22 1981-12-22 Tower packing elements

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Application Number Priority Date Filing Date Title
US06/219,311 US4327043A (en) 1980-12-22 1980-12-22 Tower packing element

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US4327043A true US4327043A (en) 1982-04-27

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DE (1) DE3150216A1 (de)
GB (1) GB2089679B (de)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5112536A (en) * 1991-03-13 1992-05-12 Koch Engineering Company, Inc. Random packing element and method
US5200119A (en) * 1985-04-11 1993-04-06 Max Leva Tower packing element
US5411681A (en) * 1993-04-19 1995-05-02 Jaeger Products, Inc. Random packing
US5543088A (en) * 1994-12-29 1996-08-06 Jaeger Products, Inc. Random packing
EP0818236A1 (de) * 1996-07-08 1998-01-14 Norton Chemical Process Products Corporation Stoffaustauschelement
US5871674A (en) * 1997-05-23 1999-02-16 Leva; Max Tower packing element
WO2002009858A2 (en) * 2000-08-02 2002-02-07 Chemineer, Inc. Static mixer element and method for mixing two fluids
US7722945B2 (en) 2006-10-10 2010-05-25 Koch-Glitsch, Lp Random packing elements and column containing same

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2157189B (en) * 1984-04-13 1987-12-16 Max Leva Tower packing element

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US912310A (en) * 1907-06-03 1909-02-16 Oscar Guttmann Filling material for reaction-spaces.
DE457966C (de) * 1925-07-03 1928-03-27 I G Farbenindustrie Akt Ges Fuellkoerper fuer Gaswaschtuerme
US1796501A (en) * 1928-09-18 1931-03-17 Berl Ernst Filling body for reaction and washing towers
US2602651A (en) * 1948-03-02 1952-07-08 Scient Dev Co Packing material
US2639909A (en) * 1951-06-29 1953-05-26 Us Stonewear Company Tower packing
DE1029346B (de) * 1955-12-13 1958-05-08 Emil Kirschbaum Dr Ing Fuellkoerper
US3266787A (en) * 1962-03-05 1966-08-16 Us Stoneware Co Pall ring
DE2821186A1 (de) * 1977-05-13 1978-11-16 Max Leva Fuellkoerper
DE2845804A1 (de) * 1977-11-01 1979-05-03 Norton Co Fuellkoerper fuer vorrichtungen zum inberuehrungbringen von gasen und fluessigkeiten
US4203934A (en) * 1975-06-13 1980-05-20 Max Leva Tower packing element

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1562402A (en) * 1976-08-18 1980-03-12 Leva M Tower packing element

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US912310A (en) * 1907-06-03 1909-02-16 Oscar Guttmann Filling material for reaction-spaces.
DE457966C (de) * 1925-07-03 1928-03-27 I G Farbenindustrie Akt Ges Fuellkoerper fuer Gaswaschtuerme
US1796501A (en) * 1928-09-18 1931-03-17 Berl Ernst Filling body for reaction and washing towers
US2602651A (en) * 1948-03-02 1952-07-08 Scient Dev Co Packing material
US2639909A (en) * 1951-06-29 1953-05-26 Us Stonewear Company Tower packing
DE1029346B (de) * 1955-12-13 1958-05-08 Emil Kirschbaum Dr Ing Fuellkoerper
US3266787A (en) * 1962-03-05 1966-08-16 Us Stoneware Co Pall ring
US4203934A (en) * 1975-06-13 1980-05-20 Max Leva Tower packing element
DE2821186A1 (de) * 1977-05-13 1978-11-16 Max Leva Fuellkoerper
DE2845804A1 (de) * 1977-11-01 1979-05-03 Norton Co Fuellkoerper fuer vorrichtungen zum inberuehrungbringen von gasen und fluessigkeiten

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5200119A (en) * 1985-04-11 1993-04-06 Max Leva Tower packing element
US5112536A (en) * 1991-03-13 1992-05-12 Koch Engineering Company, Inc. Random packing element and method
US5411681A (en) * 1993-04-19 1995-05-02 Jaeger Products, Inc. Random packing
US5543088A (en) * 1994-12-29 1996-08-06 Jaeger Products, Inc. Random packing
EP0818236A1 (de) * 1996-07-08 1998-01-14 Norton Chemical Process Products Corporation Stoffaustauschelement
US5871674A (en) * 1997-05-23 1999-02-16 Leva; Max Tower packing element
WO2002009858A2 (en) * 2000-08-02 2002-02-07 Chemineer, Inc. Static mixer element and method for mixing two fluids
WO2002009858A3 (en) * 2000-08-02 2002-04-11 Chemineer Static mixer element and method for mixing two fluids
US7722945B2 (en) 2006-10-10 2010-05-25 Koch-Glitsch, Lp Random packing elements and column containing same
US20100230832A1 (en) * 2006-10-10 2010-09-16 Koch-Glitsch, Lp Random packing elements and column containing same

Also Published As

Publication number Publication date
GB2089679A (en) 1982-06-30
DE3150216A1 (de) 1982-09-02
DE3150216C2 (de) 1991-06-27
GB2089679B (en) 1984-08-15

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